Tackle-block



u 6 e h S .W 6 8 h S 2 K N A L m JK 10 W T (No Model.)

Patented June 25, 1889.

t e e h S s t e e h S 2 KW mm L -m JK 0 W T M d 0 M o W No. 406,000.Patented June 25, 1889.

mm W grip in a different position.

UNITED STATES PATENT OFFICE.

\VILLIAM .I. LANE, OF POUGHKEEPSIE, NEXV YORK.

TACKLE-BLOCK.

SPECIFICATION forming part of Letters Patent No. 406,000, dated June 25,1889. Application filed January 12, 1889. Serial No. 296,147. (Nomodel.)

To aZZ whom it may concern:

Be it known that I, \YILLIAM .I. LANE, of Poughkeepsie, in the county ofDutchess and State of New York, have invented a new and usefulImprovement in Tackle-Blocks; and I do hereby declare that the followingis a full, clear, and exact description of the same.

My invention relates to self sustaining tackle-blocks.

My object is, first, to provide a tackle-block of this class perfectlyautomatic in its operation; second, to increase the grip on the rope;third, to prevent abrasion of the rope by the grip and to avoid anytendency of the grip to pinch the rope against narrow surfaces, wherebythe rope or some of the strands may be pinched or cut off.

My object, further, is to provide a block the grip of which shallbecapable of being made automatic in its action or be left under thecontrol of the operator.

My object, finally, is to render the block and its grip strong andcompact.

My invention is illustrated in the accompanying drawings, in whichFigure 1 shows the block and tackle in perspective. Fig. 9 is a similarview of the upper part of the block and tackle, showing the Fig. 3 is asectional view, and shows the block and tackle with the grip in twopositions. Fig. l is two transverse sections centrally through theblock. Fig. 5 is a detail view of the grip.

In the drawings, A represents the upper block, to which the grip isattached, and B the lower, and the rope is indicated at O. The blocksare composed of steel plates to c, which are connected at one end byrivets d, which pass through the blocks D, in which the hooks E areswiveled. The other ends of the steel plates are connected by means of abolt passing through interposed sleeves.

I have shown in the drawings double sheaved blocks; but it will bereadily understood that the invention is equally applicable to blockshaving single or multiple sheaves, and it is shown as applied to thesheave over which the free or drawing end of the rope is passed. V

In self-sustaining tackle-blocks heretofore known gripping devices havebeen shown in connection with the sheave adapted to bear upon theoutside of the rope and to grip by compression of the rope betweenitself and the periphery of the sheave. These have been arranged to actalso by an eccentric or wedging movement induced by the weight orresistance acting to retract the rope. My invention is based on thisgeneral principle of construction, and includes a pivoted grip whichbears against the rope on a line either above or upon, one side of adiametrical line on the sheave.

The gripping-lever is indicated at G. The particular construction whichI have shown consists of two thin bars, preferably of steel and marked 1g. These are pivoted at a point marked it on one side of the block by apivot which passes through the edges of the plates of the block, andthey are preferably located inside of the plates and between them andthe sides of the sheave. The outer ends of the bars g g are united by arivet which passes through a grippingpiece II. The pivoted ends of thesebars extend beyond the block-plates, as shown at 7.", and are united bya rivet passing through a sleeve Z, and also through a loop m. Thisextended end constitutes the short arm or pivoted end of the leverformed by the side bars 9 g and their connections. The gripping-piece isa solid block, preferably of steel, having a bearing-face formedlongitudinally on a curve nearly concentric with the outer surface ofthe rope on the sheave and with a longitudinal groove approximatelyfitting the rope. The inner face of this groove is formed with diagonalor spiral grooves corresponding approximately to the strands of rope, sothat as the block is pressed against the rope it fits upon the surfaceand forms an extended hearing, which takes hold of the rope withoutpresenting any sharp edges that bear across the fibers and tend to pinchthe fibers transversely, which might cut or rupture them. The ropepasses over the sheave and beneath the gripping-block, and in raisingthe weight is drawn in the direction indicated by the arrow shown inFigs. 1 and 2 in connection with the free end of the rope.

To obtain the full advantage of the bearing-face of the piece II, asabove described, and to obtain, also, scope of movement best fitted togrip and release it, it is necessary that the gripping-piece should movein gripping and releasing in the are of a circle larger than that of thesheaves; and for better effecting this action I have pivoted thegripping-lever G on the side of the block opposite that on which thegripping-piece is placed.

It will be noticed that the are in which the grip-block moves will not,if continued, cut or touch the periphery of the sheave or the surface atthe bottom of the groove upon which the rope rests. The path describedby the grip, however, gradually approaches the bearing-surface of thesheave as the lever follows the rope downwardly, and when the grip-piecereaches a point in line with the center of the sheave and the pivot ofthe lever the maximum amount of pressure is derived, and at this pointthe movement of the lever is arrested, as hereinafter described, andwhile the pressure exerted upon the rope is great there will not be anytendency to abrade or cut the same by reason of the fact that thegrip-surface bears squarely upon the rope throughout its extent, and theposition and path of said surface at this point is practicallyconcentric with the rope-surface.

It will be obvious that a proper pressure such as I have just1nentioned1nay be obtained by having the supporting-lever of thegripping-block pivoted at a point outside the path described by thebearing-surface of the sheave, so that the convex sides of the aresdescribed by the two surfaces would come in close proximity to eachother instead of the concave sides. The position which the lever assumeswhen the grip is loose, as in raising the load, is shown in Fig. 2, thegripping-face then bearing lightly upon the rope.

Whenever the free or drawing end of the rope is released or slackenedand the rope returns by reason of the weight, the frictional contact ofthe piece II upon the rope draws the free end of the gripping lever overa larger segment of the sheave and onto a longer segmental line, whichcauses it to bind more and more on the loop with constant-lyincreasingpressure. At the same time the gripping-piece moves on so large an anglethat it does not change its position in relation to the rope to any suchextent as to cause its sharp edges to cut across the fibers. In orderthat the movement of the gripping-lever may be arrested in gripping whena proper point of compression is attained, I provide a stop at asuitable point on the block. This may be the hub or journal of thesheave marked N, the lever being formed and extending above thehorizontal or diametrical line of the sheave to come in contact withthis hub when in proper position.

The grip may be released by a pull upon the hoisting-rope, and in orderto allow the lowering of the load when the grip is so released I providea small rope or cord 0, which is attached to the loop on the extendedend of the lever, and when the grip has been released,

, below that line.

as above stated, it may be held from action by drawing upon this rope.If it be desired that the grip shall not act automatically, a detachableweight P is attached to the loop on the short or pivoted end of thelever, which holds the grip constantly out of action so long as it ispermitted to. I

In the forms shown the gripping-lever is represented as bent, and thispermits the placing of the pivotal point on a horizontal line with thecenter of the block, or slightly The tackle-grip may be used with ropesof different sizes within reasonable limits; The gripping-surface shouldalways be at a distance from the center of the pivot,

such that the circle in which that surface moves shall extend outside ofthe bottom of the groove in the sheave a space not more than equal tothe diameter of the smallest rope that may ever be used with the block.The shape of the lever and its pivoted point is always such that whenthe gripping-block falls to a point practically the nearest to thecenter of the sheave its supporting-lever then encounters the stop.Under ordinary condition of lifting the grip spring block rests lightlyon the rope and offers no perceptible resistance to the hauling of theload. When, however, the hauling end of the rope is slackcned, itrecedes slightly and carries the grip with it, causing it to approachconstantly nearer to the periphery of the sheave, as eX- plained, theform of the gripping-surface practically fitting the surface of the ropeuntil the point is reached where the lever comes into contact with thestop. This arrests the load and sustains it. In some cases, when theload is light or the rope large or new, the

movement of the grip will be less than usual, and the rope and load willbe arrested and held without causing the grip-arms to engage with thestop.

NVhen the weight is used, as above described,

to hold the grip out of action and it is desired to grip and hold theload, a pull aside of the haulingrope, and at the same time slackeningsame, will lift the rear end of the lever and throw the grip intoengagement with the rope, and the grip will be thrown into play tosustain the load.

The length of thelever gives a strong wedging action, and thereforegreat pressure upon the rope; but by reason of the extent and form ofthe bearing-surface of the grip no injury can occur to the rope.

I am aware that levers carrying pivoted gripping-pieces loose on thelevers and pivoted on one side of the tackle are not new, and that theelements of the tackle-block have been shown in other combinations.Ithe'refore limit myself to the special combinations as below.

I claim as my invention- 1. The combination, in a tackle-block, of asheave, a gripping-block support, a gripping block fixed or non-pivotedon said support and arranged to move in proximity to the ITO sheave, thesaid support for the grippingblock being pivoted on the tackleblock at apointopposite the gripping-block, whereby the path described by thegripping-surface will be entirely outside of the bearing-s11 rface onthe sheave, the parts being constructed and arranged to operatesubstantially as described.

2. In combination with a tackle-block and a sheave, a lever pivoted uponone edge of the sheave-frame and carrying a grippingblock fixed to itsfree end and opposite the periphery of the sheave, the lever beingarranged to come into contact with the hub of the sheave when the gripis engaged with the rope, substantially as described.

3. A gripping-lever, combined with a block and its sheave, said leverbeing pivoted upon one edge of the block and arranged across the same011 one side of and above a diainetrieal line on the block, and havingalso its pivotedend extended to form a short arm of the lever, and theholding-cord 0, substantially as described.

4. Combined with a block and its sheave,

a pivoted gripping-arm having an extension at its pivoted end adapted tobe acted upon by the lifting-rope when said rope is moved out of line,substantially as described.

5. Combined with a block and its sheave, a pivoted gripping-lever havingan extension on its pivoted end arranged in the described relation tothe rope, and a detachable weight on said end, said weighted end beingadapted to be acted upon by the lifting-rope when said rope is drawn outof line to cause the grip to act, substantially as described.

In testimony whereof I have signed my name to this Specification in thepresence of two subscribing witnesses.

\V. J. LANE.

\Vitnesses;

G. H. SHERMAN, F. W. DAVIS.

